Start by dusting and lining your cake pan and also preheat your oven to 180°C
To the warm milk add the vinegar. Mix and allow it to stand for 5 mins. This is how you prepare buttermilk at home.
In the meantime, onto a bowl sieve the dry ingredients - Flour, Cocoa powder, baking soda, baking powder and salt. Set aside. (image 1)
In a separate mixing bowl, combine together oil, beetroot puree and sugar until homogenous. (image 2-3)
Start alternating between the dry ingredients and the buttermilk. Add 1/3 of the sieved dry ingredients to the mixing bowl. Mix. Add half of the buttermilk and mix again. Add another 1/3 of the dry ingredients, then the buttermilk and finally the leftover flour mixture. So you start with dry and end with dry ingredients. This is the stage to add nuts if you are using. (image 4-5)
Mix to get a cake batter like consistency and then transfer to the prepared cake pan.(image 6)
Bake in the preheated oven of 180°C for 45 to 55 mins or until a skewer inserted in the centre comes out clean.
Allow it to cool in the pan for 5 mins then transfer to a wire rack to cool completely before slicing. Feel free to dust the top with cocoa powder or icing sugar or even top it with ganache before serving.
Video
Notes
This recipe is perfect for a regular loaf tin. 8x4 inch cake tin or 9x5 inch cake tin works best. Or you can also bake it in a 8 inch round tin.
Do not add too much water while pureeing the beetroot. Try to use the weight measurements to be accurate.
Always alternate the dry and wet ingredients while mixing the cake batter starting and ending with dry ingredients. Watch the video to understand the right way of mixing the batter.
If you are using nuts, then coat the nuts with some measured out flour and then add to the batter. That way the nuts won't sink to the base of the cake while baking.
You can use the same recipe to make chocolate beetroot cupcakes too. And also layered cakes.
Needless to say common baking tips like preheating your oven before baking and dusting and lining the cake tin with parchment paper applies to this recipe as well.